Evans Strata series timpani heads feature a smooth, calf-colored coating designed to prevent timpani mallet wear and enhance the sound of the head. Strata's warm tone, clarity of pitch and articulation blend naturally with any ensemble. All Strata timpani heads are pre-tensioned with a black powder-coated insert ring for tuning consistency and additional hoop support. Available in incremental sizes ranging from 20 to 36 in.